Smart resolution valve pressure control

ABSTRACT

The Smart Resolution Valve Pressure Control System allows any pressure control system using valve state pulsing to modify airflow at an optimum and consistent range of operation thereby enhancing control accuracy and increasing the useable cycle life of any valve combination used.

FIELD OF THE INVENTION

The present invention generally relates to valve pressure control and,more particularly, relates to the valve pressure control as it relatesto brake and wheel slip control on a transit railway vehicle and, stillmore particularly, to a microprocessor for controlling the control logicof a passenger transit vehicle and, even more particularly, to amicroprocessor system designed to control the magnet valves, apply andrelease the magnet valves for proper fixed pulse timing to improve thelifecycle of these valves.

BACKGROUND OF THE INVENTION

There are known, in the prior art, many transit systems that requirebrake and/or wheel slip control and use microprocessors that run wheelslip calculations and control logic at 20 milliseconds (ms) intervals,and which generally use single 20 ms interrupts. The 20 ms interruptcontrol has proven sufficient for most applications in the past withsimpler system interfaces and larger brake cylinder pressure tolerances.However, since current and future systems are becoming moresophisticated which necessitates tighter control requirements and whichcan be used in a broader range of applications and tolerances. The useof the single 20 ms time step has become a limitation in certain presentapplications. For example, several three-state valves that were used tocontrol brake cylinder pressure have had problems maintaining stabilitywith tight tolerances, and in some configurations cannot achieve brakecylinder pressure changes as small as 1 or 2 psi. Even if the system issuccessfully calibrated to achieve these tight tolerances initially,they cannot be maintained for long time periods as the magnet valvecomponents wear.

SUMMARY OF THE INVENTION

In one aspect the present invention provides a microprocessor basedsmart resolution valve pressure control system for performing a wheelslip control valve response test. Included in the system is a sensingmeans and a begin decision means for ensuring that brakes disposed onthe truck of a vehicle are at full service and that a truck brakecylinder pressure (BCP) is greater than a first predetermined BCP. Alsoincluded is a first testing means connected to a wheel slip controlvalve for pulse releasing a wheel slip control valve to determine anelapsed time that the truck BCP drops from a second predetermined BCP toa third predetermined BCP. The system also includes a release timeadjustment means connected to the first testing means for either addingor subtracting to and from, respectively, a release time and hold timedepending on the elapsed time. Also included is a release time decisionmeans for detecting if the release time adjustment means has changed therelease time, and a reapply brake cylinder pressure means connected tothe release time decision means for enabling again the first testingmeans if the release time has changed. The system also includes anexhaust brake cylinder pressure means connected to the release timedecision means for sending a pulsed release signal and a pulsed holdsignal to a control valve and a continue decision means connectedbetween the exhaust brake cylinder pressure means and a second testingmeans for ensuring that an exhaust BCP is less than a predeterminedamount. The second testing means applies an apply pulse to a controlvalve for a predetermined time and times a BCP rise between a fourthpredetermined BCP and a fifth predetermined BCP. Also included in thesystem is an apply time adjustment means connected to the second testingmeans for either adding or subtracting to and from, respectively, anapply time and hold time depending on the time of the BCP rise betweenthe fourth and fifth predetermined BCP. An apply time decision meansconnected to the apply time adjustment means for sending either anenabling signal to a release brake cylinder pressure means connected tothe apply time decision means if the apply time has changed, or to anend wheel slip control valve test signal. The release brake cylinderpressure means, when enabled, enables again the second testing means.

Another aspect of the present invention provides a microprocessor basedsmart resolution valve pressure control apparatus used to control awheel slip control magnet valve. Included in the apparatus is a logiccontrol means for providing one of a release time and an applicationtime together with a hold time. The apparatus also includes a changedecision means connected to a logic control means for determining ifeither the release time or the application time, or the hold time havechanged since a last cycle of the apparatus used to control a wheel slipcontrol magnet valve. There is a valve timing set up means connected toa change decision means for setting either a release time, anapplication time, or a hold time if either the release time or theapplication time have changed. A pulse timing means is connected to achange decision means and the valve timing set up means for determiningif a remaining pulse time is equal to 0, and enabling a hold timingmeans if the remaining pulse time is equal to 0, and enabling a pulsetimer decrement means if the remaining pulse time is greater than 0. Thehold timing means is connected to the pulse timing means for determiningif a remaining hold time is equal to 0, and enabling a timer's resetmeans if the remaining hold time is equal to 0, and enabling a holdtimer decrement means if the remaining hold time is greater than 0. Thepulse timer decrement means and the hold timer decrement means decrementone of the remaining pulse time and the remaining hold time,respectively, and enables a valve control means. There is a timer'sreset means for resetting the pulse timing means and the hold timingmeans. The valve control means enables a magnet valve based on thecurrent pulse time or hold time, and an end interrupt routine means forending a current repetition of controlling the wheel slip control magnetvalve after either enabling the magnet valve, or resetting the pulsetiming means and the hold timing means.

Yet another aspect of the present invention provides a microprocessorbased smart resolution valve pressure control method for calibrating asmart resolution valve pressure control having a plurality of releasetimes and a corresponding plurality of hold times. The method includesapplying a release pulse of a first predetermined duration of one of aselected plurality of release times and applying a hold pulse of asecond predetermined duration corresponding to the selected plurality ofrelease times to a valve controlling the pressure to a brake cylinder,wherein the brake cylinder initially has a minimum first predeterminedpressure. The method also includes a) measuring the elapsed time thatthe brake cylinder changes from a second predetermined pressure to athird predetermined pressure, and b) increasing the first predeterminedduration and decreasing the second predetermined duration if the elapsedtime is greater than a first predetermined time, and decreasing thefirst predetermined duration and increasing the second predeterminedduration if said elapsed time is less than a second predetermined time.Also included in the method is repeating steps a) and b) if the firstpredetermined duration changes.

A further aspect of the present invention provides a microprocessorbased smart resolution valve pressure control method for calibrating asmart resolution valve pressure control having a plurality ofapplication times and a corresponding plurality of hold times. Themethod includes applying an application pulse of a first predeterminedduration of the plurality of application times and applying a hold pulseof a second predetermined duration corresponding to the selectedplurality of application times to a valve controlling the pressure to abrake cylinder, wherein the brake cylinder initially has a maximum firstpredetermined pressure. The method also includes a) measuring theelapsed time the brake cylinder changes from a second predeterminedpressure to a third predetermined pressure, and b) increasing the firstpredetermined duration and decreasing the second predetermined durationif the elapsed time is greater than a first predetermined time, anddecreasing the first predetermined duration and increasing the secondpredetermined duration if the elapsed time is less than a secondpredetermined time. Also included in the method is repeating steps a)and b) if the first predetermined duration changes.

OBJECTS OF THE INVENTION

It is, therefore, one of the primary objects of the present invention toprovide a smart resolution valve pressure control to allow any pressurecontrol system using valve state pulsing to provide an airflow ratehaving an optimum and consistent range of operation.

Another object of the present invention is to provide a smart resolutionvalve pressure control system which provides the valve-control interruptpressure commands from the calculations performed during the primarycontrol interrupt of a microprocessor.

Another object of the present invention is to provide a smart resolutionvalve pressure control system to generate the necessary valve commandsto achieve the requested pressure calculated from the primary controlinterrupt process.

Another object of the present invention is to provide a smart resolutionvalve pressure control system to communicate and interface with thevalve every millisecond instead of every 20 ms to allow a greater degreeof valve control, which improves control accuracy.

Yet another object of the present invention is to provide a smartresolution valve pressure control system to provide an accurate pressureoutput within a desired bandwidth which utilizes a smart algorithm thatrelies on a self-adjusting calibrated pulse time for a minimum pressureadjustment.

Yet another object of the present invention is to provide a smartresolution valve pressure control system to reduce the valve cyclessignificantly and to thereby increase the valve life.

Still another object of the present invention is to provide a smartresolution valve pressure control system to provide an improved shorterinterrupt control time.

Although a number of objects and advantages of the present inventionhave been described in some detail above, various additional objects andadvantages of the smart resolution valve pressure control of the presentinvention will become more readily apparent to those persons who areskilled in the art from the following more detailed description of theinvention, particularly when such detailed description of the inventionis taken in conjunction with the attached Figures and the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a combination block drawing and flow chart showing a presentlypreferred embodiment of a microprocessor based smart resolution valvepressure control system for calibration of a control process used duringregulation of the pressure in a brake cylinder during a wheel slipcondition;

FIG. 2 is a graphical illustration of Pressure Rate Request vs. Airflow(psi/sec) for a prior art new wheel slip valve;

FIG. 3 is a graphical illustration of Pressure Rate Request vs. Airflow(psi/sec) for a prior art worn wheel slip valve;

FIG. 4 is a graphical illustration of Pressure Rate Request vs. Airflow(psi/sec) for both a new and a worn wheel slip valve using the presentlypreferred smart resolution valve pressure control;

FIG. 5 is a combination block drawing and flow chart showing a presentlypreferred embodiment of a microprocessor based smart resolution valvepressure control process used when regulating brake cylinder pressureduring a wheel slip condition; and

FIG. 6 is a block diagram of hardware used in the preferred embodimentof the present invention.

DETAILED DESCRIPTION OF A PRESENTLY PREFERRED AND VARIOUS ALTERNATIVEEMBODIMENTS OF THE INVENTION

Prior to proceeding with the more detailed description of the invention,it should be noted that for the sake of clarity, identical components ofthe smart resolution valve pressure control, which have identicalfunctions, have been identified with identical reference lettersthroughout the views illustrated in the drawings.

In the presently preferred embodiment, this invention provides a methodand apparatus to allow any pressure control system using valve statepulsing to modify airflow at an optimum and consistent range ofoperation. The presently preferred embodiment of this invention alsoprovides a plurality of valve-control pressure interrupt commandsbetween the primary control interrupts of a microprocessor. Thepresently preferred embodiment of this invention also providescommunication and interface with the valve every millisecond instead ofevery 20 ms to allow a greater degree of valve control, which improvescontrol accuracy.

Reference is now made to FIGS. 1, 5, and 6. Illustrated therein is apresently preferred embodiment for calibration of a smart resolutionvalve pressure controller, generally designated 10. FIG. 6 is a blockdiagram of the hardware, generally designated 100, which supports FIGS.1 and 5. In the presently preferred embodiment, a microprocessor basedcalibration system 10 for a smart resolution valve pressure controlsystem for a control valve comprises a microprocessor 102, a brakecylinder pressure detector 108, and a brakes full service statusdetector 104 in FIG. 6, and in FIG. 1, a sensing means 12 for ensuringthat brakes disposed on a truck of a vehicle (such as a subway car) areat full service and the truck brake cylinder pressure is at least 60psi. It will be understood that in the preferred embodiment the sensingmeans 12 includes the brakes full service status detector 104, the brakecylinder pressure detector 108 and algorithms in the microprocessor 102.The creation of this algorithm and other algorithms implied in FIGS. 1and 5 are within the ability of someone skilled in the art ofmicroprocessor software design.

Connected to the sensing means 12 is a begin decision means 16 whichenables a first message communicator means 14 if the brakes are not infull service or the brake cylinder pressure (BCP) is less than 60 psi.The first message communicator means 14 includes a visual display 110,used for sending a wheel slip response test message “W/S Response NotRun; Pressure Improper” when a BCP is improper, or the brakes are not infull service as indicated by the sensing means 12.

The begin decision means 16 enables a first testing means 18 when thebrakes are in full service and the BCP is at least 60 psi. The firsttesting means 18 includes a wheel slip three-state brake control valve106. With the brakes in full service and a BCP of at least 60 psi, thecontrol valve 106 is pulse released at one of the pressure rate requestvalues from 1 through 7, for example a pressure rate request value of“4”, for 1 second. The elapsed time for a pressure drop between 55 psiand 5 psi is determined for use by a release time adjustment means 22.

Connected to the first testing means 18 is the release time adjustmentmeans 22 for adding to, or subtracting from, a release time and holdtime depending on the elapsed time determined by the first testing means18. More particularly, the release time adjustment means 22 determinesif the time determined by the first testing means 18 is greater than 750ms, in which case 1 ms is added to the current release time and 1 ms issubtracted from the current hold time. The release time adjustment means22 also determines if the elapsed time is less than 720 ms in which case1 ms is subtracted for all the release times of the current pressurerate request value, and 1 ms is added to the current pressure raterequest hold time. The release time adjustment means 22 also restrictsthe minimum times of the release and hold times to 7 ms. The releasetime adjustment means 22 also ensures that the current pressure raterequest value has a total release time and hold time of 160 ms.

A release time decision means 24 monitors the activities of the releasetime adjustment means 22 and sends an execution signal to either areapply brake cylinder pressure means 26 or an exhaust brake cylinderpressure means 28. If the release time adjustment means 22 adjusts therelease time (and hold time), then the release time decision means 24enables the reapply brake cylinder pressure means 26, otherwise itenables the exhaust brake cylinder pressure means 28. The reapply brakecylinder pressure means 28 re-enables the first testing means 18.

The exhaust brake cylinder pressure means 28 sets the valve 106 to fullrelease for 1 second followed by a 1 second hold, after which theexhaust brake cylinder pressure means 28 detects if the BCP is less than1 psi.

Connected to the exhaust brake cylinder pressure means 28 is a continuedecision means 32 which enable a second message communicator means 42 ifthe BCP, after the 1 second release and 1 second hold, is greater than 1psi. The second message communicator means 42 includes the visualdisplay 110, used for sending a wheel slip response test message “W/SResponse Not Run; Release Improper” when the BCP is greater than 1 psi.

The continue decision means 32 enables a second testing means 34 whenthe BCP is less than 1 psi. The second testing means 34 includes thewheel slip three-state brake control valve 106. With the BCP less than 1psi the control valve 106 is pulse released at one of the pressure raterequest values from 9 through 15, for example a pressure rate requestvalue of “12”, for 1 second. The elapsed time for a pressure risebetween 5 psi and 50 psi is determined for use by an apply timeadjustment means 36.

Connected to the second testing means 34, the apply time adjustmentmeans 36 adds to, or subtracts from, an apply time and hold timedepending on the elapsed time determined by the second testing means 34.More particularly, the apply time adjustment means 36 determines if theelapsed time from the second testing means 34 is greater than 1080 ms inwhich case 1 ms is added to the current apply time and 1 ms issubtracted from the current hold time. The apply time adjustment means36 also determines if the elapsed time is less than 1050 ms in whichcase 1 ms is subtracted from the current apply time, and 1 ms is addedto the current hold time. The apply time adjustment means 36 alsorestricts the minimum times of the apply and hold times to 7 ms orgreater. The apply time adjustment means 36 also verifies that thecurrent pressure rate request value has a total apply time and hold timeof 140 ms.

An apply time decision means 44 monitors the activities of the applytime adjustment means 36 and either enables a release brake cylinderpressure means 38 or ends the interrupt and the calibration of the smartresolution pressure controller. If the apply time adjustment means 36adjusts the apply time (and hold time), then the apply time decisionmeans 44 enables the release brake cylinder pressure means 38, otherwiseit ends the calibration. The release brake cylinder pressure means 38re-enables the second testing means 34.

Graphically illustrated in FIG. 2 is the pressure rate request vs.airflow for a prior art example of airflow control based on a valvecontrol sequence with a 20 ms repetition rate for a brand newthree-state wheel slip control valve 106 as shown in Table 1: TABLE 1Pressure Rate Request Value Definition Operational Valve State 15 FullFlow Continuous Apply, 0 ms Hold application −110 psi/sec 14 86 psi/sec120 ms Apply 20 ms Hold 13 71 psi/sec 100 ms Apply 40 ms Hold 12 55psi/sec 80 ms Apply 60 ms Hold 11 39 psi/sec 60 ms Apply 80 ms Hold 1024 psi/sec 40 ms Apply 100 ms Hold 9 8 psi/sec 20 ms Apply 120 ms Hold 8Hold - 0 psi/sec 0 ms Apply/Release Continuous Hold 7 −9 psi/sec 20 msRelease 140 ms Hold 6 −26 psi/sec 40 ms Release 120 ms Hold 5 −44psi/sec 60 ms Release 100 ms Hold 4 −61 psi/sec 80 ms Release 80 ms Hold3 −79 psi/sec 100 ms Release 60 ms Hold 2 −96 psi/sec 120 ms Release 40ms Hold 1 −114 psi/sec 140 ms Release 20 ms Hold 0 Full Release −140Continuous Release 0 ms Hold psi/sec

Graphically illustrated in FIG. 3 is the pressure rate request vs.airflow for a prior art example of airflow control for an old wheel slipthree-state control valve 106 as shown in Table 2: TABLE 2 Pressure RateRequest Value Definition Operational Valve State 15 Full Flow ContinuousApply, 0 ms Hold application −110 psi/sec 14 79 psi/sec 120 ms Apply 20ms Hold 13 63 psi/sec 100 ms Apply 40 ms Hold 12 47 psi/sec 80 ms Apply60 ms Hold 11 31 psi/sec 60 ms Apply 80 ms Hold 10 16 psi/sec 40 msApply 100 ms Hold 9 0 psi/sec 20 ms Apply 120 ms Hold 8 Hold - 0 psi/sec0 ms Apply/Release Continuous Hold 7 0 psi/sec 20 ms Release 140 ms Hold6 −18 psi/sec 40 ms Release 120 ms Hold 5 −35 psi/sec 60 ms Release 100ms Hold 4 −53 psi/sec 80 ms Release 80 ms Hold 3 −70 psi/sec 100 msRelease 60 ms Hold 2 −88 psi/sec 120 ms Release 40 ms Hold 1 −105psi/sec 140 ms Release 20 ms Hold 0 Full Release −140 Continuous Release0 ms Hold psi/sec

Due to the increase of the dead time characteristics in the wheel slipthree-state brake control valve 106 as its cycle life progresses, thevalve's flow for pulsed operation is offset so much that pressure rateresponse 8, pressure rate response 9, and pressure rate response 10 haveno airflow. Only pressure rate response 9 should have no airflow, andcontinuation of the trend illustrated in FIG. 3 will result in increaseddegradation of the wheel slip control performance.

Graphically illustrated in FIG. 4 is the pressure rate request vs.airflow for both the new and worn wheel slip control valves using thepresently preferred smart resolution valve pressure control for athree-state wheel slip control valve 106 as shown in the followingtables 3 and 4: TABLE 3 (New Valve) Pressure Rate Request ValueDefinition Operational Valve State 15 Full Flow Continuous Apply, 0 msHold application −110 psi/sec 14 90 psi/sec 125 ms Apply 15 ms Hold 1375 psi/sec 105 ms Apply 35 ms Hold 12 60 psi/sec 86 ms Apply 54 ms Hold11 45 psi/sec 67 ms Apply 73 ms Hold 10 30 psi/sec 48 ms Apply 92 msHold 9 15 psi/sec 29 ms Apply 111 ms Hold 8 Hold - 0 psi/sec 0 msApply/Release Continuous Hold 7 −14 psi/sec 26 ms Release 134 ms Hold 6−32 psi/sec 47 ms Release 113 ms Hold 5 −50 psi/sec 67 ms Release 93 msHold 4 −68 psi/sec 88 ms Release 72 ms Hold 3 −86 psi/sec 108 ms Release52 ms Hold 2 −104 psi/sec 129 ms Release 31 ms Hold 1 −122 psi/sec 149ms Release 11 ms Hold 0 Full Release −140 Continuous Release 0 ms Holdpsi/sec

TABLE 4 (Worn Valve) Pressure Rate Request Value Definition OperationalValve State 15 Full Flow Continuous Apply, 0 ms Hold application −110psi/sec 14 90 psi/sec 133 ms Apply 7 ms Hold 13 75 psi/sec 115 ms Apply25 ms Hold 12 60 psi/sec 96 ms Apply 44 ms Hold 11 45 psi/sec 77 msApply 63 ms Hold 10 30 psi/sec 58 ms Apply 82 ms Hold 9 15 psi/sec 39 msApply 101 ms Hold 8 Hold - 0 psi/sec 0 ms Apply/Release Continuous Hold7 −14 psi/sec 16 ms Release 144 ms Hold 6 −32 psi/sec 37 ms Release 123ms Hold 5 −50 psi/sec 57 ms Release 103 ms Hold 4 −68 psi/sec 98 msRelease 62 ms Hold 3 −86 psi/sec 139 ms Release 21 ms Hold 2 −104psi/sec 153 ms Release 7 ms Hold 1 −122 psi/sec 153 ms Release 7 ms Hold0 Full Release −140 Continuous Release 0 ms Hold psi/sec

Referring now to FIG. 5, illustrated therein is an apparatus 20 used ina valve control sequence to control a wheel slip control magnet valveduring normal 1 ms interrupt operations after calibration of the smartresolution pressure controller. A primary control interrupt occurs every20 ms and calculates a current pressure rate request value which is usedduring the normal 1 ms interrupt operations. A logic control means 46provides the current pressure rate request value to a pressure raterequest change decision means 48. The pressure rate request changedecision means 48 receives data from the logic control means 46 anddetects if the pressure rate request value is new. A valve timing set upmeans 52 is enabled by the pressure rate request change decision means48 for setting (i.e., storing in the microprocessor 102) a pulse state,a pulse timer and a hold timer if the pressure rate request value isnew. The terms “pulse state” and “pulse timer” includes a release stateand release timer if the pressure rate request value provided by thelogic control means 46 calls for a brake release pulse, and alsoincludes an application state and application timer if a brakeapplication pulse is required by the pressure rate request value.

A pulse timing means 54 is energized by either the pressure rate requestchange decision means 48, if there is no change in the pressure raterequest value, or the valve timing set up means 52, if there is a newpressure rate request value. Pulse timing means 54 stores in themicroprocessor 102 the previous interrupt remaining pulse time if thereisn't a new pressure rate request value, or changes to a new pressurerate request pulse time and hold time if there is a new pressure raterequest value. The pulse timing means 54 detects if the remainingpressure rate request value pulse time is greater than zero. If so, thepulse timing means 54 does not energize a hold timing means 56, butrather enables the pulse time decrement means 62 which, in turn, passesthe pulse command (either release or apply) to a valve control means 66which, in turn, sends a pulse enable signal to the wheel slipthree-state brake control valve 106 and ends the interrupt to themicroprocessor 102.

If the pulse timing means 54 has a pulse time remaining of 0, the pulsetiming means 54 enables the hold timing means and does not energize thepulse time decrement means 62.

The hold timing means 56 checks the previous interrupt's remaining holdtime stored in the microprocessor 102. The hold timing means 56 detectsif the remaining pressure rate request value hold time is greater thanzero. If so, the hold timing means 56 does not enable a timer's resetmeans 58, but rather enables a hold timer decrement means 64 which, inturn, passes the hold command to the valve control means 66.

If the remaining time in the hold timer means 56 is zero, the holdtiming means 56 enables the timer's reset means 58 and does not enablethe hold timer decrement means 64. The timer's reset means 58 resets thepulse timing means 54 and the hold timing means 56 to the currentpressure rate request values. The timer's reset means 58 either (1) endsthe interrupt to the microprocessor 102 by bypassing a closed loop feedback means 68 depending on whether the apparatus 20 uses a user testmethod of calibration such as shown in FIG. 1, in which case the closeloop feedback means 68 would be bypassed as indicated by the dashed linein FIG. 5 and the calibrations process of FIG. 1 would be manuallyenabled by a user, or (2) enables a calibration process by the closedloop feedback means 68.

In the presently preferred embodiment, the overall control is based on a20 ms interrupt software program control. In the prior art, a pressurerate request value of 12, for example, would be 80 ms Apply (4 times 20ms) and 60 ms (3 times 20 ms) Hold. Advantageously, in the preferredembodiment of the present invention use of additional 1 millisecondinterrupts allows the pressure rate request value of 12, for example, tobe adjusted to values such as 74 ms Apply and 66 ms Hold (not limited tomultiples of 20 ms). Additionally, through use of the smart resolutionvalve pressure control 10, the pressure rate request value of 12 couldundergo frequent tuning that could vary the time of the apply pulse andhold pulse such that the pressure rate request value would consistentlygive the same airflow rate over the valve's cycle life. Note that oneskilled in the art could easily place this calibration in the actualvalve control sequence using closed loop feedback.

Also the presently preferred embodiment of this invention provides theability of the smart resolution valve pressure control to provideaccurate pressure outputs to the wheel slip three-state brake controlvalve which are within a desired bandwidth. The present inventionutilizes an apparatus that relies on a self-adjusting calibrated pulsetime for a minimum pressure adjustment. Through the use of amicroprocessor based smart resolution valve pressure control system thevalve cycles are reduced significantly thereby increasing the valve lifecycle. The valve lifecycle is increased by avoiding alternate releaseand apply operations when the airflow is near 0 psi.

While both the presently preferred and a number of alternativeembodiments of the present invention have been described in detail aboveit should be understood that various other adaptations and modificationsof the present invention can be envisioned by those persons who areskilled in the relevant art without departing from either the spirit ofthe invention or the scope of the appended claims.

1-9. (canceled)
 10. An apparatus used to control a wheel slip controlmagnet valve, said apparatus comprising: a) a logic control means forproviding one of a release time and an application time together with ahold time; b) a change decision means connected to said logic controlmeans for determining if said one of a release time and an applicationtime, and said hold time have changed since a last cycle of saidapparatus used to control a wheel slip control magnet valve; c) a valvetiming set up means connected to said change decision means for settingsaid one of a release time and an application time, and said hold timeif said one of a release time and an application time have changed; d) apulse timing means connected to said change decision means and saidvalve timing set up means for determining if a remaining pulse time isequal to 0, and enabling a hold timing means if said remaining pulsetime is equal to 0, and enabling a pulse timer decrement means if saidremaining pulse time is greater than 0; e) a hold timing means connectedto said pulse timing means for determining if a remaining hold time isequal to 0, and enabling a timer's reset means if said remaining holdtime is equal to 0, and enabling a hold timer decrement means if saidremaining hold time is greater than 0, said pulse timer decrement meansand said hold timer decrement means for decrementing one of saidremaining pulse time and said remaining hold time, respectively, and forenabling a valve control means, said timer's reset means for resettingsaid pulse timing means and said hold timing means; f) a valve controlmeans connected to said pulse timer decrement means and said hold timerdecrement means for enabling a magnet valve based on one of said pulsetime and said hold time; and g) an end interrupt routine means connectedto said valve control means for one of ending a current repetition ofcontrolling said wheel slip control magnet valve after one of saidenabling said magnet valve, and resetting said pulse timing means andsaid hold timing means.
 11. An apparatus used to control a wheel slipcontrol magnet valve, according to claim 10, said apparatus furtherincluding a closed loop feedback means disposed between said timer'sreset means and said end interrupt routine means to recalibrate acurrent pulse time and a current hold time, if necessary.
 12. Anapparatus used to control a wheel slip control magnet valve, accordingto claim 10, wherein said one of a release time and an application timeand said hold time correspond to one of a plurality of pressure rateresponse values.
 13. An apparatus used to control a wheel slip controlmagnet valve, according to claim 10, wherein said pulse state, pulsetime and hold time are stored in a microprocessor. 14.-19. (canceled)